Filler cap for gasoline tanks



Sept. 23, 19 o. H. GRISWOLD 2,611,503

FILLER CAP FOR GASOLINE TANKS Filed Feb. 18, 1949 2 SHEETS-SHEET l I r INVEN TOR.

III I owe/v h. (12/5 WOLD MAU Patented Sept. 23, 1952 I UNITED STAT ES PAT E NT OFFICE FILLER CAP FOR GASOLINE TANKS Owen H.-Griswold, Ridgewood, N. .J. Application February 18, 19.49,.Serial No. 77,239

. .1 This invention :relates, as .indicated to a filler capfor fuel, oil, ethylene glycol and water alcohol tanks of all sizes and types, but has reference "more particularly to a cap designed especially for use'in connection with-standard fittings for filler cap attachment-to self-sealing and conventional =tanksiof both military and commercial aircraft. Aprimary object of the invention is to provide a'filler 'cap of the character described, which will "not leaknndervari'oustestpressures or under the higher "hydraulic ram pressures resulting from gun fire into the fuel tanks of aircraft, as prescribed bythe Air Forces of the United States.

Another object of the invention is to provide a 'cap 'of the character described, the "operation of which presents the least possible chance for "human error.

Another object of the invention is to provide acap-of the character described, which, after installation, cannot be misplaced.

A further object of the invention is to provide new of the characterdescribed, which can be quickly and easily securedor released.

A further object-of the invention is to provide a cap of the character described, which, when used on pressurized fuel tanks, cannot blow *off and thereby cause damage to material and personnel.

Other objects of the invention are to provide 'a cap which can be used to replace previous 'designs, nowin service, without alterations to surrounding structures, to provide a cap which coma typical or conventional airplane wing; showing atfuel tank'provided with the tank filler cap of the present invention;

Fig. 2 is attop plan view of'the tank filler cap;

Fig. 3.isra "fragmentary view, partly in elevationandpartly in section, taken on the line -3--3 of Fig. 2;

Fig.4 is a cross-sectionalview of the filler cap, taken on the line 4-4 (if-Fig.5;

Fig. 5'is a 'cross-sectional'view, taken on the line 5-5 .of Fig. 4;

13 Claims. (Cl. 220-) Fig. 6 is a view showing the position of the cap, when fully open; 7

Fig.7 is a view similar to Fig. Gjbu't of the -.reverse side of the cap;

Fig. 8 is a perspective view of the slider'assembly of the filler cap;

Fig. 9is a bottom plan 'view. of a portion of the adaptor, and

Fig. 10 is a transverse cross-sectional view of the adaptor, showing one of the cam slots.

Referring'rmore particularly to the drawings. reference numeral I designates a fuel'tank in an airplane, the upper wall or which is disposed below the skin S of the airplane. This cell or tank has a filler opening defined by an annular fitting 2, which is secured to the tank in the man ner shown in 'Fig; 3,-this fitting, which is part of the tank, being one of the type known as AN 4130-7 (Air Force-Navy Aeronautical stand ards), or a similar fitting. Access :to the filler cap, in this case, may-be had through an access door ('not shown), provided in the skin S, directly above thefiller -cap,-'or,:the cap can be mounted flush with the skin contour.

Secured to theupper surface oi? the fitting 2, as

by screwsor-bolts 3, is a filler cap, comprising an adaptor l'in the form of a metallic disc having an annular "outer edge 5 and anannular inner edge 6, in eccentric relation to the outer edge. The adaptor has a flange 1 which extends downwardly into the filler opening defined .by the fitting 2, the inner edge of this flange forming an openingfi? which is a continuation .of the inner edge 6 of the adaptor. The .flange 1 varies .in thickness, as shown in Fig. 9, from a minimum at the point A, to a maximum at the points B, which are slightly more than degrees from the point A, and rearwardly of the points B the fiange decreases in thickness, and is provided with a pair of spaced-parallel ears-0r lugs 9. The ears 9 extend somewhat below the lower edge of the flange-I, and serveapurpose to be presently described.

The flange 1 isprovided-at diametrically opposite points adjacent the points B, with cam slots or grooves which communicate with "the opening 8v defined by the flange, and have vertical portions 10 and inclined .portions 1 ll extending from theupper ends of the portions [0.

A portion of the upper face of the adaptor isremoved'to provide a seat or ledge for ahandle l5, which, when seated, has its upper-surface substantially flush with the upper surface of the adaptor. .Theadaptor is further formed with a beveled surface 18 whichior-msafingefihole for 3 lifting the handle I5, when the filler cap is to be opened.

The handle is in the form of a segment of a disc, which, in seated or closed position, covers a portion of the opening 8 in the adaptor, and is provided with a stem i'l extending from the chordal edge of the handle, the upper surface of this stem being flush with that of the handle. Extending downwardly from the stem (7 of the handle is a pair of parallel spaced ears i3, having openings l9 therein for the reception of a pivot pin 29, the ends of which are mounted in a pair of spaced guides 2i.

The guides 21 are also in the form of segments of discs, the chordal edges of which extend at right angles to the chordal edge of the handle H5. The upper surfaces of these guides, when in closed position, cover those portions of the opening 8 in the adaptor which are not closed by the handle l5 and stem ll of the handle. Portions of the guides are cut away, as at 2 2, for the reception or seating of the handle 15, when the latter is in closed position.

'I'heears it are also provided with openings 23, which are spaced both longitudinally and vertically from the openings (9, and have mounted thein a pin 24, to which a slider assembly, generally designated by reference numeral 25, is pivotally secured. This slider assembly comprises a link 28, one end of which is connected to the pin 26, and the other end 2'! of which extends angularly to the remainder of the link, and is connected, as by a rivet 28, to a slider 29 and a slider dog 38, the slider dog and slider being also connected toeach other, as by a rivet 31. The slider dog has ends 32 which are bent angular-1y to the plane of the dog, these ends being normally disposed in the cam slots H.

The slider 29 is normally disposed in a slot or groove 33 which extends diametrically across the upper face of a circular base member 3%. The base member 34 has a lower surface, the central portion 35 of which is flat and'parallel with the upper surface of the base member, and the, outer portion 36 of which is conical. Extending downwardly from the flat surface. 35 is an elongated tenon 31, which extends in a direction at substantially right angles to the long dimension of the slot or groove 33.

The guides 2! are secured to the base member 34 by means of rivets 38. A rubber seal 39, of a contour similar to that of the outer surface of the flange l of the adaptor, is secured to the lower surface of the base member 34, with the tenon two screws 43 which extend through an elongated slot 44' in the pressure plate and into tapped openings in the tenon' 31. The heads of these screws bear against a hinge 45, which is disposed below the pressure plate, in spaced relation to the latter, and a leaf spring i6 is interposed between the'upper surface of this hinge and the lower surface of the pressure plate. A seal clamping plate 41 bears against the lower surface of the seal, and is retained in clamping position by means of cylindrical spacers '48, which extend through the slot 44 in the pressure plate, and are interposed between the clamping plate and hinge 45.

The hinge G5 is pivotally connected to a hinge pin 49, which is mounted in the ears 9 of the adaptor.

It will be noted that the rivet 28 has an elongated head 513, the lower end of which bears against the slider dog 3ll,-and the other end of which is upset to providea flangeil. The end 2'1 of the link 28 is connected to the head 50 of the rivet and has limited movement along this head, between the slider dog and the flange 5|, the connection being, in effect, a lost-motion connection.

The screws G3 are locked against rotation, by means of a wire 52 which interconnects the heads of the screws.

There is also provided a, locking spring 53, which interconnects bosses 54 which project downwardly from the guides 21. This sprin is arcuate in form, to conform with the arcuate out,-

.er edges of the guides 21, and has inturned ends 55, which embrace the bosses 5 3 of the guides. It will be noted that the screws .43 exert pressure on the hinge 45, spacers 48 and, clamping plate 41. This leaves the peripheral portion of the seal 39 with a limited degree of flexibility relative to the conical portion surfaceilt of the base member 35, there being a clearance of approximately 0.03 inch between the seal and the periphery of the surface 36. The rubber seal 39 is a synthetic of the Buna, N class, and of all the types of rubbers, it is the one least affected by contact with aromatic fuels, while still retailiing the desired mechanical properties. The Government specification for this rubber permits a volumetric increase or swell of 50% when in contact with aromatic fuel audit is therefore necessary to allow space for this expansion while maintaining pressure on the rubber to hold the seal. This accounts for the necessity of having the spring 46 apply force through the floating pressure plate 42 to maintain pressure between the seal 39 and the adaptor flange l. The elasticity of the rubber cannot be relied upon to maintain pressure under conditions of F. and the action of aromatic fuels. .In addition, under production conditions, it is; possible that the bottom 35 of the base member 34 .may be above or below the sealing surface of flange 7. If it were below, the rubber seal 39 would be held away from flange I, thus breaking the seal.- To prevent this, the surface3$ has been made conical, with the clearance of 0.03." at its edge, which permits the plate 42 to press the peripheral portion of the seal 39-. against flange I while holding it rigidly at its center under the clamping plate 47. Thus, the seal would assume a, concave shape, due to its flexibility, and thereby maintain the sealing .contact. When the tank contains pressure and the cap is opened, the seal assumes the above conical shape up to the .03, but as the cap is fcrceddown more than .03, the outer edge of base 34 makes contact with rubber seal 39 and additional downward travel forces it away from'flange 1. Due to the-use of the internal (tank) pressure to aid rather than oppose the sealing, it is necessary to use the mechanical advantage of the mechanism to supply the necessary force. The spring 45 is also positioned by contact of the spacers G8 with diametrically opposite points or crotches in the spring 48. -While neitherplate 4|, nor spring 46 are restrained axially, "they'are limited in their axial 'travlzinone direction by means of the hinge 1 55, and in the opposite direc= tion, they exert :pressure on the :peripheral portion of theseal.

I-he operation of :the cap may be briefly described, as follows: V

Assuming that :the cap is in closed positionas showninl igs. 2,. 3,54 and 5, the operation is as follows: The handle lfiis 'lifted'bytinserting the finger into the finger-ilrole Hiyand by using the finger under the handle which has been thus initially lifted. To facilitate finsertion of 'the finger under the hand1e,the handle :is provided on its underface withabeveled surface 56, which isdisposedadjacent'the'surfaoe it. As the handleiisthus lifted, the pin 12% is caused to rotate about the pin 2fi, causing the slider assembly to be drawn toward the pin .20. This, in turn, causes :the ends 32 of 'thesliderdog to be moved along the inclined portions H of the cam slots in the adaptor, thereby forcing the cap down- Wardl-y relatively to theadaptor and forcing the sealiiS "out of engagement with its seaton the adaptor, that is .to say, .out of engagementwith the lower end of the flange I. This is possible because the flexibility f the seal is limited, as above-stated, to approximately 05.03 *inch before coming into contact with the periphery of the base member 34, while the vertical movement of th'excap, due to the inclination of thecam-slots in the adaptor, is approXirnatelyOlQ inch. *After the handle has been rotated through an angle of from 80 to 1-00 degrees relatively to'the adaptor, the =ends-32 of the slider dog are disposed above'the vertical portions of the cam slots, permitting the cap assembly to "fall, by gravity, inwardly, the cap assembly pivoting about the hinge pin 49. As the cap assembly falls, it assumes a vertical position relatively to the adaptor, as viewed in broken lines in Fig. 3, and in Figs. 6 and '7, due to rotation of the cap assembly relatively-to the handle I5 about the pin 24. In this. way. the handle l5 above the adaptor is at an angle of approximately 90 degrees to the plane of the adaptor (or skin covering), and serves as a warning "that the cap is open. Since themajor dimension of the handle is a chord of the circular opening in the adaptor, which "opening, in the usual case, is about 3 inches in diameter, "the handle, in the open position, 'ofiers a minimum restriction, from the aerodynamical standpoint. g

The cap is closed by pulling'the handle upwardly-until the ends 32"of the slider dog enter the vertical portions "ill of thecam slots in the adaptor, and then pushing the'handle forwardly until the handle is flush withthe adaptor and cap assembly. As'the'handle is thus being moved to closed position, the .curvedend of the slider 29 comes into contact with the center .of the spring 53. Due to the relative positions of pins and 24 and the point of contact of the link 26 with the rivet head 5!, the pressure of the spring 53 on the slider assembly tends to rotate the handle [:5 in a clockwise direction, as viewed in Fig. 4, thereby holding the handle against the shoulders 22 of the guides 2|. This is necessary to counteract the tendency of vibration and other accelerative forces to open the cap.

It is thus seen that I have provided a filler cap for fuel tanks, which has a number of distinct advantages over filler caps heretofore available.

(a) The cap will not leak under test pressures of pounds per square inch, and under only one side of. the moss bar under its roam or 1 dog, anditiwas also possible to rotate ;the cap through-ran: angle less *thansufiicien'ta JED 100k .it', and in either Tease, vibration. could cause :the, cap to be lost: :Under :both of these COIldi'tiOIlS5xafih8 cap iwasifiushtwith the skin :covering :of: the rail-- planegand. appeared toibe imposition. '1=here:are

several cases on record :in which. thisihas caused the loss -:of anairplaneby fire. The cap;- of :the present inventionimust :bie'i locked, or the capiand handle will not .berflush with the skin covering, so that the-locked condition is readilyapparent, eliminating even a remote :possibility :of human error.

"(c) 'Thecap cannotbemisplaced. In previous designs,"the cap has-been held inplace by a-chain extending from the cap .through the filler opening and attached tothe 1adaptor or seat internally. These, in general, havepro-ved unsatisfactory. j

(d) The cap isquickly and easily :secured :or released. The hinge; design of the mechanism guides theucap into :the zadaptor,ymaking it unnecessaryto feel for the cam openings, :as ,in previous designs. iMoreover, the lever action makes for'easier applicationaofforcesfor opening and closing, than the torque or twisting :action required in previous designs.

(e) The cap, when used on pressurized'tanks, cannot blow off, when released, and thereby :cause damage to material :and personnel. In some previous designs, the cap cannot be opened against-pressure, because of jamming, whereas, in the present cap, the mechanical advantage of the'lever and slope of-the cam slots in theradaptor is utilized 'to'accomplish this in aneasy and positivemanner.

" (7) The cap can be used to replace-previous designs, "now in service, without alterations-to surrounding structure.

(g) "The cap compensates for dimension changes in'the *rubberseal, due .to aromatic and other fuels, and -'to temperature changes.

01 The cap is lig'hter. in weight than the standard designs now in use.

It is to be understood that 'the'form of my invention, herewith shown and described, 'is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of my invention, orthe scope of the subj'oined-claims. 5

Having thus described my invention, I claim:

1. In a' filler cap for fuel receptacles, an adaptor having a filler opening, a closure for said opening, said closure being pivotally secured to said adaptor, and a closure operator, said closure operator including a handle, a member pivotally secured to said handle, and a slider having a lostmotion connection with said member and slidable transversely of said closure, and means in said adaptor connected to said slider for camming said closure to closed position.

2. In a filler cap for fuel receptacles, an adaptor having a filler opening, a closure for said opening, said closure being pivotally secured to said adaptor, guides connected to said closure and movable therewith, said guides defining. a track therebetween, a closure operator comprising a handle pivotally securedto s'aid'guides and a-slide member operatively connected to said handle, said slide member beingslidable in said track.

3. In a filler cap for fuel receptacles. an adaptor having a filler opening and cam slots in the wall of said openingya closure for said opening, said closure being pivotally secured to. said adaptor, guides connected to said closure and movableth'erewith, said guidesdefining a track therebetween, a closure operator comprising a handle pivotally secured to-said. guides, anda slide assembly operatively connected to said handle, said guide assembly including a member slidable in said track, and a memberhaving. en portions movable in said cam slots.

4. A filler cap, as defined in claim 3, in which said handle is so shaped that, in association with said guides, it forms a secondary closure for said opening, said handle having a Width greater than the diameter of said filler opening, whereby said handle is'pr'ecludd at all times from fallin through said opening.

5. A filler cap, as defined in claim 4, in which said slide assembly-is pivotally connected to said handle. 6. In a filler cap for fuel tanks, a member-having afiller opening and a downwardly facing seating surface, a closure p'ivotally connected to said member andincluding means for seating against said surface, said closure, when in its fully open position, being disposed in a plane substantially perpendicular to the plane of said member and below the plane of said seating surface, and means for moving said closure from said fully open position to a closed position in which said seating means is in contact with said surface, said means including a rigid handle operatively connected to said closure and movable in its entirety in an are normal to the plane of said member during said closure-closing operation, said handle being entirely free of any connection to said member and being of a width greater than the diameter of said filler opening, whereby it rests on the upper edgeof said member when the closure is in fully open position and cannot fall through said opening.

7. A filler cap, as defined in claim 6, in which said member has cam slots therein, andsaid closure moving means is provided with elements movable in said cam slots during movement of the closure between said positions.

8. A filler cap, as defined in claim '7, in which said camslots have vertical and inclined portions, said vertical portions permittin the closure to fall by gravity when said elements are disposed therein.

9. In a filler cap for fuel receptacles, an adaptor having a filler opening, a closure pivotally connected to said adaptor and having sealing means adapted to be moved into sealing contact with said adaptor, said closure, when in fully open position, being disposed in a plane substantially perpendicular to the plane of said adaptor, and means for moving said closure from said fully open position to a closed position in which said sealing means is in contact with said adaptor, said means including a handle supported by said adaptor, operatively connected to said closure and movable in an are normal to the plane of said adaptor during said closure closing operation, said connection including an element slid able transversely of said closure relatively to said closure during said movement.

10. A filler cap, as defined in claim 9, in which said adaptor has cam slots therein, and said closure operating means has elements movable in said cam slots during said movement.

11. A filler cap, as defined in claim 10, in which said transversely slidable element includes a slider dog having ends movable in said cam slots.

12. A filler cap, as defined in claim 11, in which said handle has a surface which lies substantially flush with the upper face of the adaptor when said closure is in closed position.

13. In a filler cap for fuel receptacles, an adaptor having a filler opening and a downwardly facing seating surface, a hinge pivotally connected to said adaptor, a closure carried by said hinge and comprising a rubber seal adapted to bear against said surface and close said opening, a pressure plate having a peripheral; flange bearing against the peripheral portionof said seal, a resilient member carriedby said hinge and interposed between said hinge and pressure plate, whereby said pressure plate is caused to bear resiliently against said rubber seal, and a base membercarried by said hinge and having a central portion which bears against said rubber seal, and an outer or peripheral portion having a conical surface spaced from said rubber seal.

OWEN H. GRISWOLD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS,-

Italy Feb. 4, 1927 

